Variable stoke pusher for plating and like machines



Dec. 7, 1954 c. s. CLARK 2,695,122

VARIABLE STROKE PUSHER FOR PLATING AND LIKE MACHINES Filed Aug. 9, 1951 2 Sheets-Sheet 1 I N VEN TOR.

(A g sfer 65 (Var f W ZJW 7, 1954 c. e. CLARK 2,696,122

VARIABLE STROKE PUSHER FOR PLATING AND LIKE MACHINES Filed Aug. 9, 1951 2 Sheets-Sheet 2 lo W 4 A Ty. a

LIN, 1 1

INVENTOR.

* 6/):5ter Clark United States Patent VARIABLE STROKE PUSHER FOR'PLATING AND LIKE MACHINES Chester Graham Clark, Detroit, Mich., 'assignor to The Udylite Corporation, Detroit, Mich., a corporation of Delaware Application August 9, 1951, Serial No. 241,147

4 Claims. ((31. 74-110 The present invention pertains to a work pusher mechanism of the reciprocating type as distinguished from a continuous mechanisnrof the chain type. The invention is adapted especiallyto plating apparatus although it may be used in conveying apparatus of various types.

A reciprocating pusher .mechanism .is shown in the United States patent to John V. Davis, No. "2,479,322 of August 16, 1949. Pusher bars are located atsuitable positions along the work rail and are linked together and to their actuator in such a manner that all have equal and simultaneous displacements. The pusher bars carry pusher fingers that move the work carriers on the rail from which the carriers are suspended.

In some instances unequal displacements of adjacent pusher bars is desirable. In treating material in an alined series of tanks, as in plating for example, the work in a given tank may advantageously have a greater or smaller travel than in an adjacent tank. Again, where a smaller travel is advantageous or even permissible in a given tank, this tank may be correspondingly shortened, witlh a corresponding economy in floor space and matena.

The principal object of this invention is to provide a mechanism whereby two adjacent pusher bars may be given unequal strokes although propelled by a common actuator. To accomplish this object, only one of the pusher bars is connected directly to the actuator and is joined to the other pusher bar by a novel linkage. A cam track runs alongside the pusher bars and has one portion spaced farther than the other from the common axis of the pusher bars. The link connections between the bars consist of a pair of simple links pivoted to the bars at one end and pivoted together at the other end. At said other end is a roller that rides in the cam track.

The cam track is so positioned that the movement of the directly actuated bar causes the roller to ride from the nearer to the farther portion of the track, or vice versa. In the former case, the movement of the roller from the nearer to the farther part of the cam track reduces the angle between the links. The result is that the pusher which is actuated through the links receives a shorter stroke than the pusher that is directly actuated. The work moved by the pusher of shorter stroke is necessarily more closely spaced, in keeping with the considerations described above.

The invention is fully disclosed by way of example in the following description and in the accompanying drawings in which:

Figure 1 is a side view of the device;

Figure 2 is a plan view thereof;

Figure 3 is a similar view in a different position;

Figure 4 is a corresponding side elevation, partly in section; and

Figures 5, 6, 7 and 8 are sections on the lines 5--5, 66, 77 and 8-8 respectively of Figure 4.

Reference to these views will now be made by use of like characters which are employed to designate corresponding parts throughout.

In Figure 1 is shown a series of tanks 1 separated by partitions 2 and containing various solutions such as cleaners, plating solutions and rinses in a plating operation. Over the tanks is a rail 3 from which is suspended a suitable number of slidable work carriers or books 4. At suitable points over the rail, alined shoes 5, opening downwardly, are secured to the fixed structure A. These members are of channel section with inturned edges and slidably support the pusher bars 6 which are of 2,696,122 Patented Dec. 7, 1954 FYICC T-section. The edges 0f the bars areobviouslymouflted in the shoes, and-the webs lie vertical. Pusher fingers 7 are pivotally attachedto the webs 8 of the bars-6 pins 9. Each finger is preferably notched at '10 onits advance side and directly below the web so that it may slide'idly over a hook 4 onthe retraction stroke in order to engage the same hook for pushing, as shown in Figure 4.

Any suitable means may be provided for oscillating-the pusher bar '6. For example, as in the aforementioned copending application, a fluid cylinder 11 has a piston rod 12 connected by alink 13 to an ear 1-4' on the pusher bar. The double acting valve arrangement for the'cylinder for automatically reversing thedirectionof the piston therein is well known in the art and therefore not disclosed here.

Acam track is fixed to the frame structure A-and overlaps the space between two pusher bars 6 and '6' acting on the carrierhooks in two adjacent tanks. A portion 15 of the trackis spaced farther than the remaining portion 16 from'the common axis of the, pusher'bars and both portions are preferably parallel to this axis. The portion 15 .lies adjacent'to the tank in which the pusher 6' is operative,. and it :is to be noted that this pusher is not connected directly to the actuating mechanism.

The connection between the pusher bars consists of a pair of links 17 pivotally attached at one end by pins 18 to the respective bars. The remaining ends are pivotally attached to each other by a pin 19 which also carries a roller 20 riding in the cam track. The latter is preferably of channel construction with retaining strips 21 extending inward from the edges over the roller 20.

Let it be assumed that the work is pushed from left to right and that a shorter displacement of the work is to be effected at the bar 6, for one of the reasons previously set forth. The pusher fingers on the bar 6' are correspondingly spaced. The bar 6, being directly connected to the actuator mechanism, has a stroke of fixed length. At some point in the stroke, the roller 20 rides from the nearer track portion 16 to the more remote portion 15. The angle between the links 17 is thereby made smaller, and the pusher bars 6 drawn closer to the bar 6. The overall work stroke of the bar 6 is reduced according to the reduction of the distance between the bars and the tank in which the bar '6 operates may be made correspondingly shorter.

Where such shorter travel of the work is desirable or permissible, a corresponding economy in floor space and structural materials may be realized. The invention may also be used for longer than normal travel. If the operation in a given tank requires longer travel than in the majority of tanks in the series, the cam track at the given tank is set closer than the remainder of the track to the pusher bars.

Although a specific embodiment of the invention has been illustrated and described, it will be understood that various alterations in the details of construction may be made without departing from the scope of the invention as indicated by the appended claims.

What I claim is:

1. A variable stroke pusher mechanism for moving work along a carrier rail, comprising a pair of slidably mounted alined and spaced pushers, means for directly reciprocating one of said pushers, a cam track overlapping the space between said pushers, said track including portions lengthwise of and unequally spaced laterally from said pushers and having a connecting portion joining the first named portions, said first named portions being spaced from each other lengthwise of said pushers, a pair of links pivotally connected to the respective pushers and to each other, a guide member at the common pivotal connection of said links and riding in said track and connecting portions, said track and connecting portions confining said guide member against transverse movement therein.

2. A variable stroke pusher mechanism for moving work along a carrier rail, comprising a pair of slidably mounted alined and spaced pusher bars, pusher fingers pivoted to said bars and extending transversely therefrom, means for directly reciprocating one of said bars,

a cam track overlapping the space between said pushers, said track including portions lengthwise of and unequally spaced laterally from said bars and having a connecting portion joining the first named portions, said first named portions being spaced from each other lengthwise of said bars, a pair of links pivotally connected to the respective bars and to each other, a guide member at the common pivotal connection of said links and riding in said track and connecting portions, said track and connecting portion confining said guide member against transverse movement therein.

3. A variable stroke pusher mechanism for moving work along a carrier rail, comprising a pair of slidably mounted alined and spaced pushers, means for directly reciprocating one of said pushers, a cam track over- T.

lapping the space between said pushers, said track ineluding portions lengthwise of and unequally spaced laterally from said pushers and having a connecting portion joining the first named portions, said first named portions being spaced from each other lengthwise of said pushers, a pair of links pivotally connected to the respective pushers and to each other, a guide member at the common pivotal connection of said links and riding in said track and connecting portions, the track portion having the smaller spacing from said pushers being dis- 1 posed adjacent to the directly reciprocated pusher, said track and connecting portions confining said guide member against transverse movement therein.

4. A variable stroke pusher mechanism for moving Work along a carrier rail, comprising a pair of slidably mounted alined and spaced pusher bars, pusher fingers pivoted to said bars and extending transversely therefrom, means for directly reciprocating one of said bars, a cam track overlapping the space between said pushers, said track including portions lengthwise of and unequally spaced laterally from said bars and having a connecting portion joining the first named portions, said first named portions being spaced from each other lengthwise of said bars, a pair of links pivotally connected to the respective bars and to each other, a guide member at the common pivotal connection of said links and riding in said track and connecting portions, the track portion having the smaller spacing from said bars being disposed adjacent to said directly reciprocated bar, said track and connecting portion confining said guide member against transverse movement therein.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,165,985 Schwenthler July 11, 1939 2,320,259 Brassel May 25, 1943 2,575,396 Schenk Nov. 20, 195i 

